Unmanned aircraft



FIG. 1 is a top plan view of the unmanned aircraft employing our design;

FIG. 2 is a front elevation view of the aircraft shown in FIG. 1;

FIG. 3 is a side elevation view of the same aircraft;

FIG. 4 is a perspective view of the same aircraft.

The broken line disclosure in the figures is illustrative of a propeller path. 

The ornamental design of an unmanned aircraft, substantially as shown and described. 